Untitled

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>It works!</title>
  <script>
    var handleClick = function() {
      var ownBody = document.getElementsByTagName('body')[0]
      var iframe = document.createElement('iframe');
      iframe.setAttribute('style', 'display: none');
      iframe.addEventListener('load', function(e) {
        var response = e.target.contentWindow.document.getElementsByTagName('body')[0].innerText;

        console.log('got response', response)

        document.getElementById('output').innerText = response;

        ownBody.removeChild(iframe)
      })
      iframe.src = 'someApi?user=A&score=1'

      console.log('before request')

      ownBody.appendChild(iframe);

      console.log('after request')
    };

    document.addEventListener('DOMContentLoaded', function() {
      document.getElementById('send').addEventListener('click', handleClick);
    })
  </script>
</head>
<body>
  <pre id="output"></pre>

  <input id="send" type="button" name="submit" value="Get it!" />
</body>